Damper assembly



Nov. 21, 1961 F. H. RICHTERKESSING EI'AL 3,009,475

DAMPER ASSEMBLY 2 Sheets-Sheet 1 Filed Sept. 14. 1959 v INVENTORS FRANK H. QICHTERKESSING AUGUST A. BRIAN ATTORNEY Nov. 21, 1961 F. H. RICHTERKESSING EI'AL 3,

DAMPER ASSEMBLY 2 Sheets-Sheet 2 Filed Sept. 14, 1959 INVENTORS FRANK H. RICHTERKESSING AUGUST A. BRIAN BY uasmwg ATTORNEY United States Patent Ofifice 3,009,475 Patented Nov. 21, 1961 3,009,475 DAMPER ASSEMBLY Frank H. Richterkessing and August A. Brian, Louisville,

Ky., assignors to W. M. Cissell Manufacturing Compauy, Louisville,.Ky., a corporation of Kentucky Filed Sept. 14, 1959, Ser. No. 839,662 Claims. (Cl. 137512.1)

This invention relates to vent dampers and more particularly to automatically operable dampers for assembly in a vent conduit of the type used in the venting of automatic clothes drying machines. Such conduits generally are of an inexpensive tubular sheet metal construction and, for commercial reasons, require a damper assembly whose cost is in reasonable proportion to the cost of the rest of the conduit while at the same time being entirely reliable in operation.

An object of the invention is to provide an improved inexpensive, reliable damper assembly for use in vent conduits.

Another object is to provide an improved damper assembly having a construction permitting fabrication by simple metal working techniques, and installation by relatively unskilled labor requiring no use of tools.

Other objects and advantages will become apparent as the description proceeds and when considered in conjunction with the accompanying drawings in which:

FIG. 1 is an exploded view showing a vent conduit with one form of damper assembly in position to be mounted in a generally vertical position therein.

FIG. 2 is a plan view to a larger scale of the damper assembly shown in FIG. 1.

FIG. 3 is a sectional view taken on line 33 of FIG. 2 and with the vanes in closed position.

FIG. 4 is a view similar to FIG. 3 and with the vanes in open position.

FIG. 5 is a detail view to a larger scale showing the elongated portion of one bracket in engagement with the shoulder.

FIG. 6 is a detail view in plan of the bracket shown in FIG. 5.

FIG. 7 is an exploded view showing a. modified damper assembly for use in a non-vertical position.

FIG. 8 is a front elevation view to a larger scale of the modified damper of FIG. 7; and

FIG. 9 is a sectional view taken on line 99' of FIG. 8, but showing the vanes of the modified damper in open position.

In accordance with the invention, a tubular member which is insertable between two other tubes of a vent conduit contains two butterfly damper vanes pivotally mounted therein and which are adapted to seat while in closed position upon a circumferential inner shoulder formed in the tubular member. The shoulder, as well as a bead to limit axial telescoping of the conduit members toward each other, and one or more crimped ends of the tubular member, are all spaced from each other so that they may be formed simultaneously in the single blank which is used in fabrication of the tubular member. Moreover, the blank used in forming the vanes also may include integral portions serving as brackets for mounting the vanes; all to contribute to an inexpensive and reliably operating damper assembly.

Referring first to FIG. 1, the damper assembly generally shown at 10 is adapted for connection to the ends of cooperating tubes 11 and 12 serving as a vent conduit arranged in a generaly vertical direction and with the damper assembly being movable to closed position by gravity- The tubular wall of the damper assembly may comprise any suitable material such as sheet metal and may be formed by conventional metal working techniques from a flat sheet which is later bent into tubular form and with its axial edges secured to each other along an area 13 as by means of rivets or welding. Prior to bending the sheet into tubular form, it is pressed within suitable dies to form, preferably simultaneously, an inwardly directed shoulder 14, a bead 15 which may be either inwardly or outwardly directed and one or more crimped end portions 16. The respective crimped end, shoulder, and bead portions are spaced from each other sufiiciently far to permit the simultaneous working of the three die elements, but, in general, the overall length of the tubular member is relatively short in comparison with the companion tubes of the conduit.

Mounted within the thus described tubular member is a pair of butterfly-type vanes 17 and 18, each having a flat face portion including a substantially serni-circular peripheral edge adapted to seat in its entirety upon shoulder 14 and also a straight edge portion extending substantially diametrically of the tubular member. These vanes also may be made of sheet meta-l and are provided with integral bracket members struck out of the sheet forming the vane and bent into planes normal to the plane of that sheet. These bracket members are disposed at the ends of the straight edges of the vane 17 and 18, as seen at 20, 21 and 22, 23, respectively. Also bent from the plane of the sheets forming the vanes but in a downwardly extending plane generally normal to the plane of these sheets and along the straight edges of the vanes are integral sealing skirts, as shown at 24 and 25. These skirts abut against each other when the damper is closed as best seen in FIG. 3 and are appropriately cut away at their ends to clear the shoulder 14, as seen, for example, at 26 in FIG. 6.

Various means may be employed for pivotally mounting the vanes in operative position within the tubular member, one such means being shown as a single rod 27 mounted at its ends in the walls of the tubular member and at an appropriate height above shoulder 14. This rod extends through suitable apertures formed in the respective brackets at such location as will permit the swinging of the vanes upwardly into substantially vertical planes as seen in FIG. 4 when gas pressure is applied through the lower conduit section 12.

As a feature of the invention, one of the brackets on each vane, as shown at 20 and 23, includes an elongated portion 30 (FIG. 5) which engages against the upper side of shoulder 14 when the corresponding vane is fully lifted, thus to prevent that vane from travelling over dead center and falling into closed position on top of the other vane when the pressure in the conduit is later reduced. The companion brackets 21 and 22, however, do not contain the elongated portion and are disposed inwardly of the brackets which do contain those elongated portions. Moreover, the location of the mounting rod 27 is such that the mass of each vane lies on one side of the axis of the tubular member when that member is assembled with the axis thereof vertical, thus biasing each vane to fall by gravity against shoulder 14- when gas pressure in the conduit is reduced.

For use in conduits which are arranged horizontally or at an incline such that gravity operated closing is unreliable, the invention may be employed with a structure such as seen in FIGS. 7 to 9. In this modification, a damper assembly of the type generally shown at is adapted for connection to the ends of cooperating tubes 11 1 and 112. As in the earlier described type of damper, an inwardly directed shoulder 114, a bead and a crimped end portion '116 are provided and are spaced sufficiently far apart to permit simultaneous forming of the same.

Mounted within the thus formed tubular member is a pair of butterfly-type vanes 117 and 118, each having a fiat face portion including a substantially semi-circular peripheral edge adapted to seat in its entirety upon shoulder 11 4 and also a straight edge portion extending substantially diametrically of the tubular member. These vanes 117 and 11 8 likewise are made of sheet metal and are provided with the above-described type of bracket members as seen at 120, 121 and 122, 123, respectively.

Also bent from the plane of the sheets forming the vanes, but facing upstream in a direction generally normal to that plane and along the straight edges of the vanes are sealing skirts as shown at 124 and 125. An elongated rod 127 mounted at its ends in the walls of the tubular member and at an appropriate distance down stream from shoulder 114 serves as a support upon which the vanes are pivotally mounted. This rod extends through apertures in the respective brackets, one of each pair of which, as above-described, has an elongated portion which is engageable with the shoulder 114, as seen at 130 in FIG. 9, when the vane is in fully opened position. When the vent conduit extends generally horizontally, the axis of the rod preferably is located in a generally vertical plane.

Loosely surrounding rod 127 is an elongated torsion spring 131 having ends 132 and 133 coacting with the respective vanes normally to hold the same in closed positon upon shoulder 114. These ends may be spot welded to the vanes, if desired, but as an alternative, by merely extending the terminal ends of the spring through small apertures in the vanes, a satisfactory springing action may be secured in an inexpensive manner.

Accordingly, when the spring loaded assembly is mounted in a generally horizontal vent conduit, the vanes are held in closed position as seen in FIG. 8 while gas pressure is reduced in conduit 111, but move to open position as seen in FIG. 9 when sufiicient gas pressure is applied in that conduit.

Having thus described the two modifications of the damper assembly, the several practical features of construction embodied therein will be readily apparent. By means of its compact construction, a reduced amount of stock material is required for the tubular member and inventory space is minimized. The integrally formed bead serves to position the assembly in proper relation to the connected conduit sections and prevents those sections from telescoping toward each other. The integral shoulder serves as a major reinforcement for the assembly as well as a seat against which the vanes may rest. The two vanes are mirror-images of each other and may be stamped by means of a single die. The mounting, including the bracket arrangement, provides an assembly which is reliable in operation as well as inexpensive in construction.

From the above description it will be seen that various changes in the proportions or shaping of parts may be made without departing from the spirit or scope of our invention; and it will be understood that the above description is considered as being illustrative of, rather than limitative upon, the invention defined by the appended claims.

What is claimed is:

1. For use in a conduit comprising a pair of spaced conduit sections adapted to connect therebetween with a complementary relief valve unit and through which a fluid under pressure is adapted to be passed; the improvement comprising a relief valve unit including a generally cylindrical tube having an inwardly disposed circumferential shoulder integrally formed in said tube intermediate the ends thereof, a pair of interchangeable butterfly vanes adapted to rest normally in closed position upon said shoulder, each of said vanes having a substantially semi-circular peripheral edge adapted to seat upon said shoulder together with a straight edge extending substantially diametrically of said tube, a bracket at each end of each of said vanes integrally formed with the respective vanes and located at the extremity of said straight edges of said vanes, said brackets being located in planes generally normal to the planes of said vanes and extending downstream of said tube, one bracket on each of said vanes being adapted to engage the shoulder of said tube during the movement of its corresponding vane to fully opened position, and means mounted in the walls of said tube downstream of said shoulder and pivotally and jointly supporting in pairs the respective brackets of each of said vanes whereby upon application of suflicient fluid pressure in said tube upstream of said vanes, said vanes are moved to open said tube and upon reduction of said pressure, said vanes move to closed position on said shoulder.

2. Apparatus as defined in claim 1 wherein said one of said brackets on each vane includes an elongated portion engageable with said shoulder at approximately the full opening position of its associated vane, the respective elongated brackets on the vanes being disposed at diametrically opposite sides of said shoulder.

3. Apparatus as defined in claim 2 wherein the respective brackets having said elongated portions are mounted closer to the inner surface of said tube than the brackets which do not have said elongated portions.

4. Apparatus as defined in claim 1 wherein each of said vanes includes a skirt portion normally extending upstream along the straight edge thereof and forming a member in abutting relation to the corresponding member on the other vane when said vanes are in closed position.

5. For use in a conduit comprising a pair of spaced conduit sections adapted to connect therebetween with a complementary relief valve unit and through which a fluid under pressure is adapted to be passed; the improvement comprising a relief valve unit including a generally cylindrical tube having an inwardly disposed circumferential shoulder integrally formed in said tube intermediate the ends thereof, a pair of interchangeable butterfly vanes adapted to rest normally in closed position upon said shoulder, each of said vanes having a substantially semi-circular peripheral edge adapted to seat upon said shoulder together with a straight edge extending substantially diametrically of said tube, a bracket at each end of each of said vanes integrally formed with the respective vanes and located at the extremity of said straight edges of said vanes, said brackets being located in planes generally normal to the planes of said vanes and extending downstream of said tube, one bracket on each of said vanes being adapted to engage the shoulder of said tube during the movement of its corresponding vane to fully opened position, a single rod mounted in the walls of said tube downstream of said shoulder and pivotally and jointly supporting in pairs the respective brackets of each of said vanes, and a torsion spring loosely supported upon said rod and having its ends engaging with the respective vanes whereby upon application of sufiicient fluid pressure in said tube upstream of said vanes, said vanes are moved against the action of said spring to open said tube and upon reduction of said pressure, said vanes move under the action of said spring into closed position on said shoulder.

References Cited in the file of this patent UNITED STATES PATENTS 1,238,878 Bavo Sept. 4, 1917 1,413,371 Adler Apr. 18, 1922 1,508,922 Cawley Sept. 16, 1924 1,743,731 Scott Jan. 14, 1930 2,358,101 Randall Sept. 12, 1944 0 58 Herbage Sept. 22, 1959 

